The production of chemicals by the gasification of coal has been a goal of research for many years. In particular, it has been desired to produce linear oxygenates (e.g. alcohols and aldehydes) from carbon monoxide and hydrogen. Usually, the production of these desirable compounds is accompanied by the production of linear hydrocarbons, usually n-paraffins.
Many catalysts have been suggested to perform this conversion. In U.S. Pat. Nos. 4,122,110 and 4,291,126 there are disclosed catalysts which are said to be capable of converting synthesis gas to oxygenates in yields over 90%. These catalysts are four component mixtures which include copper, cobalt, a third metal selected from chromium, iron, vanadium and manganese, and at least one alkali metal. Coprecipitation techniques are used and the resultant catalyst is dried at 200.degree.-600.degree. C. Attempts to repeat these results by others have not been successful. References are made to Courty et al, "C.sub.1 -C.sub.6 Alcohols Production from Syngas", Symposium on Chemicals from Syngas and Methanol, 191.sup.st ACS National Meeting, Apr. 13-18, 1986 and Courty et al, J. Molec. Catal. 17, 241 (1982).
Other catalysts have also been suggested. In U.S. Pat. No. 4,440,668, there is disclosed a catalyst which contains copper, cobalt, an alkali metal and zirconium.
In U.S. Pat. No. 4,119,656, there is disclosed a catalyst that includes palladium.
In French Pat. No. 1,074,045 there is disclosed the use of precipitated catalysts which include a major portion of copper and a minor portion of a metal of the iron group with the possible addition of activators such as alkali metals, zinc or chromium. A mixture of the oxides of copper, iron and potassium is disclosed. However, there is no disclosure of the crystal structure of these catalysts.
The present invention provides an alternative catalyst of unique crystal structure. The catalysts of the present invention display excellent selectivity to the production of higher oxygenates.